The best way to do this is to remove the redshirt, leave him off the depth chart so he doesn’t play at all, and then redshirt him after the championship game. This is much better in two ways for most players. First (less relevant for you), you don’t lose all these WE points up front, he still grows. It does still matter for IQ, though not as noticeable as if he still had significant growth left elsewhere.
The big thing for you is that leaving the redshirt off until the end of the season will let you recruit with extra scholarship resources for his spot. Your AD thinks he’s graduating. You’ll get the cash next season, too, when he actually graduates.